A MOS (Metal Oxide Semiconductor) field effects transistor (MOSFET) adopts an embedded SiGe (eSiGe) structure in which a SiGe (silicon germanium) layer is embedded in a source/drain region of a p-channel MOSFET (PMOSFET). A lattice constant of SiGe is larger than a lattice constant of Si, and hence a compressive strain is applied to a channel region sandwiched in between the source/drain regions in which the SiGe layer is embedded. In this case, a Hall mobility of the channel region is improved with the result that a current drive capability of PMOSFET rises, thereby enabling an improvement of characteristics of PMOSFET to be realized.
For example, an oxide film is grown as an insulation film by CVD (Chemical Vapor Deposition) on a silicon substrate, and the silicon substrate is etched with the oxide film serving as a mask, thereby forming a recess (recess well) in the surface of the silicon substrate exposed from the oxide film. Then, the SiGe layer is selectively epitaxially-grown in the recess, thus forming eSiGe structure in the silicon substrate.    Japanese Laid-open Patent Publication No. 2009-094225